Application of AERMOD on near future air quality simulation under the latest national emission control policy of China：A case study on an industrial city

Air quality model can be an adequate tool for future air quality prediction, also atmospheric observations supporting and emission control strategies responders. The influence of emission control policy (emission reduction targets in the national "China’s 12th Five-Year Plan (2011-2015)") on the air quality in the near future over an important industrial city of China, Xuanwei in Yunnan Province, was studied by applying the AERMOD modeling system. First, our analysis demonstrated that the AERMOD modeling system could be used in the air quality simulation in the near future for SO2 and NOx under average meteorology but not for PM10. Second, after evaluating the simulation results in 2008 and 2015, ambient concentration of SO2, NOx and PM10 (only 2008) were all centered in the middle of simulation area where the emission sources concentrated, and it is probably because the air pollutions were source oriented. Last but not least, a better air quality condition will happen under the hypothesis that the average meteorological data can be used in near future simulation. However, there are still heavy polluted areas where ambient concentrations will exceed the air quality standard in near future. In spatial allocation, reduction effect of SO2 is more significant than NOx in 2015 as the contribution of SO2 from industry is more than NOx. These results inspired the regulatory applications of AERMOD modeling system in evaluating environmental pollutant control policy     

火球热辐射改进计算模型

为对火球热辐射影响范围进行合理的计算和危险后果进行合理评价,借鉴点源模型和计算流体力学CFD思想,建立了火球热辐射改进计算模型,并与点源模型进行了对比。结果表明:改进模型比传统的点源模型计算结果偏大,特别是距离火球较近处。随着半径的增加,2种模型的计算结果趋于统一。当测量点的半径大于火球半径的2倍时,可以使用点源模型进行热辐射量的计算,满足工程精度要求;在近火球位置,点源模型精度较差,须用改进模型进行计算。建立的改进计算模型可以实现火球热辐射的快速计算,是有效、可行的。     

农村环境监测存在的问题及建议——以敖其村为例

通过对敖其村地表水、饮用水源地、环境空气、土壤进行调查,发现作物种类改变、监测点位变化、专业人员匮乏、经费来源紧张等问题制约了农村环境质量监测工作的开展,建立固定监测点位、加强人员培训、加大经费投入等措施可以有效解决农村环境质量监测中存在的问题,保证监测工作的顺利开展和进行。     

北京市医院环保验收内容及注意事项

根据建设项目竣工环境保护验收规范要求,针对北京市医院环保验收内容,总结了此类项目的验收工作重点,并具体阐述了医院废水监测、医疗废物管理、环境管理检查等工作实施中的注意事项。     

On‐Site Exposure to Treated Wastewater Effluent Has Subtle Effects on Male Fathead Minnows and Pronounced Effects on Carp

This study tested the hypotheses that (1) exposure to treated Water Reclamation Plant (WRP) effluent will induce biological effects in exposed fish that are consistent with environmental estrogen (EE) exposure; and (2) seasonal differences in effluent composition will moderate biological effects. We conducted seven on‐site exposures using a mobile laboratory. Total estrogenicity of effluents was 10‐ to 20‐fold higher during spring than in fall. Common EEs including steroid estrogens, alkylphenols, and bisphenol‐A were ubiquitous. An unusual spike in total estrogenicity identified a combined sewer overflow event. Fathead minnows (Pimephales promelas) responded to exposure with subtle changes in vitellogenin concentrations and secondary sex characteristics. An opportunity to assess a common carp (Cyprinus carpio) population permanently sustained inside the Stickney WRP revealed pronounced exposure effects, but also the resilience of biological organisms even under long‐term exposure. In contrast to other studies, no histopathological changes were found. The mobile exposure laboratory proved capable of maintaining U.S. Environmental Protection Agency‐recommended exposure conditions while providing flexibility for rapid deployment at multiple sites with minimal operational disruption. Further studies using this platform hold promise to resolve the convoluted interactions between complex effluents and inherent biological complexity.     

“Nutrient Inputs to the Laurentian Great Lakes by Source and Watershed Estimated Using SPARROW Watershed Models” by Dale M. Robertson and David A. Saad2

Richards, R. Peter, Ibrahim Alameddine, J. David Allan, David B. Baker, Nathan S. Bosch, Remegio Confesor, Joseph V. DePinto, David M. Dolan, Jeffrey M. Reutter, and Donald Scavia, 2012. Discussion –“Nutrient Inputs to the Laurentian Great Lakes by Source and Watershed Estimated Using SPARROW Watershed Models” by Dale M. Robertson and David A. Saad. Journal of the American Water Resources Association (JAWRA) 1‐10. DOI: 10.1111/jawr.12006 Abstract: Results from the Upper Midwest Major River Basin (MRB3) SPARROW model and underlying Fluxmaster load estimates were compared with detailed data available in the Lake Erie and Ohio River watersheds. Fluxmaster and SPARROW estimates of tributary loads tend to be biased low for total phosphorus and high for total nitrogen. These and other limitations of the application led to an overestimation of the relative contribution of point sources vs. nonpoint sources of phosphorus to eutrophication conditions in Lake Erie, when compared with direct estimates for data‐rich Ohio tributaries. These limitations include the use of a decade‐old reference point (2002), lack of modeling of dissolved phosphorus, lack of inclusion of inputs from the Canadian Lake Erie watersheds and from Lake Huron, and the choice to summarize results for the entire United States Lake Erie watershed, as opposed to the key Western and Central Basin watersheds that drive Lake Erie’s eutrophication processes. Although the MRB3 SPARROW model helps to meet a critical need by modeling unmonitored watersheds and ranking rivers by their estimated relative contributions, we recommend caution in use of the MRB3 SPARRROW model for Lake Erie management, and argue that the management of agricultural nonpoint sources should continue to be the primary focus for the Western and Central Basins of Lake Erie.     

The Design of a New Energy-conservation Type Solar-powered Lighting System Using a High‐pressure Sodium Lamp

This study designs and applies a new energy-conservation type solar-powered lighting system using a high-pressure sodium lamp to areas not having any utility company's electricity. The proposed system uses a zero-voltage-switching (ZVS) DC/DC converter in the batteries’ charge circuit to reduce the switching loss for a higher charging efficiency. Said system also adopts the maximum power point tracking (MPPT) technique to maximize the solar panels’ photovoltaic conversion capability. When dark, the batteries in the proposed system will discharge, with a raised voltage, through a push-pull DC/DC converter; said voltage, as the input voltage of the series-parallel resonant inverter, will be regulated to dim the lamp. To enable the efficient usage of the batteries’ stored energy capacity, this control scheme of the proposed system may adjust the night-time discharge time lengths, according to season difference, and compute the usable capacity for the load, according to the batteries’ charged voltage, so as to select a suitable pre-scheduled light-dimming curve for the lamp to achieve energy conservation for the batteries and continuity in lighting when dark.     

基于热爆炸理论的煤燃点确定及动力学分析

为准确判断煤燃点,提高煤自燃灾害防治能力,依据热爆炸理论,结合煤自燃过程放热曲线,将煤自燃升温过程中微分热流曲线上第1处极小值点作为煤的燃点,计算煤着火前后放热过程动力学参数变化.结果表明:随升温速率增加,煤自燃反应放热过程逐渐向高温区域移动,煤燃点逐渐增大,反应的活化能逐渐减小;同一升温速率下燃点之后煤的活化能增大;...     

基于PNN的煤矿安全生产风险综合预警研究

为加强煤矿安全生产风险预警管理,对煤矿安全生产系统风险因素进行分析,从人-机-环-管理四个方面建立了风险预警指标体系,给出了各指标的定义;提出了指标风险预警等级临界点的设置和指标警度计算方法;应用概率神经网络（PNN）构建了安全生产风险综合预警模型,通过指标风险预警等级临界点构建训练样本,并对预警模型进行了性能检验和工程应用。结果表明,基于PNN的安全生产风险综合预警模型风险识别能力强,运行速度快,计算效率高,可以进行推广应用。     

Development of a method to predict crash risk using trend analysis of driver behavior changes over time

Objective: This study aimed at identifying and predicting in advance the point in time with a high risk of a virtual accident before a virtual accident actually occurs using the change of behavioral measures and subjective rating on drowsiness over time and the trend analysis of each behavioral measure.

Methods: Behavioral measures such as neck bending angle and tracking error in steering maneuvering during the simulated driving task were recorded under the low arousal condition of all participants who stayed up all night without sleeping. The trend analysis of each evaluation measure was conducted using a single regression model where time and each measure of drowsiness corresponded to an independent variable and a dependent variable, respectively. Applying the trend analysis technique to the experimental data, we proposed a method to predict in advance the point in time with a high risk of a virtual accident (in a real-world driving environment, this corresponds to a crash) before the point in time when the participant would have encountered a crucial accident if he or she continued driving a vehicle (we call this the point in time of a virtual accident).

Results: On the basis of applying the proposed trend analysis method to behavioral measures, we found that the proposed approach could predict in advance the point in time with a high risk of a virtual accident before the point in time of a virtual accident.

Conclusion: The proposed method is a promising technique for predicting in advance the time zone with potentially high risk (probability) of being involved in an accident due to drowsy driving and for warning drivers of such a drowsy and risky state.